Abstract:

Abstract:Objective To investigate the curvature radius of distal femur and hypocondyle by imageological methods and compare the differences between them and gender differences between male and female,and provide morphological basis for design of knee joint prosthesis.Methods  69 cases of normal knee undergoing magnetic resonance imaging in knee extensor 180 ° position were selected in sagittal images,the anterioposterior dimension (AP),rd and rh were measured and the medial curvature index(MCI),lateral curvature index(LCI),distal condyle curvature index (DCI) and hypocondyle curvature index(HCI) were used as the curvature standards of distal femur and the femoral posterior condylar.Results The rd of male medial condyle was (32.58±4.84)mm,rh was (19.04±3.33)mm;rd of male lateral condyle was (32.82±3.95)mm,rh was (19.38±2.80). The rd of female medial condyle was (29.40±4.15)mm,rh was (15.99±2.38)mm;the rd of female lateral condyle was (29.30±3.16)mm,rh was (16.41±2.01)mm. The data showed statistical difference in MCI and LCI between male and female (P<0.05).There was statistical difference between female DCI and HCI (P<0.05).The result of  two-variable linear regression analysis showed the linear regression between AP,rh and rd (P<0.001).Conclusion There are statistical differences in distal femur and hypocondyle curvature between male and female.The curvature of female is larger,especially the medial hypocondyle.It is suggested that the asymmetry curvature design should be taken for the prosthesis’s hypocondyle part,that is,the curvature of medial distal condyle should be increased to form a continuous radius design with the medial hypocondyle which has larger curvature.

Key words: femur;hypocondyle;curvature radius